Eight measures to eliminate static electricity in chemical tank areas

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How to eliminate static electricity? Security experts point out that there are two main ways to eliminate static electricity: one is to create conditions that accelerate the leakage of static electricity or its neutralization ； Second, control the process to limit the generation of static electricity. Given the characteristics of hazardous chemical storage areas, the prevention and control of static electricity mainly includes the following points: 1. Static electricity grounding. Grounding is the simplest and most common method for eliminating static electricity hazards, and it is primarily used to remove static electricity from conductors. People can take proper grounding measures in accordance with **standards and industry norms to prevent the generation of static sparks. 2. Humidification. Increasing the relative humidity in the air helps to eliminate static electricity present at the site. As the relative humidity in the air increases, certain amount of moisture is absorbed or adsorbed on the surface of objects, reducing their surface resistance and thus facilitating the discharge of static electricity into the ground. While increasing air humidity to eliminate static electricity, it should not be done at the expense of human health, equipment damage, or the quality of hazardous chemicals; generally, a relative humidity of around 70% is sufficient to significantly reduce static electricity accumulation. 3. Add an antistatic agent. Antistatic agents have good electrical conductivity or strong moisture absorption. In the chemical industry, salts such as acid salts, naphthenate salts, chromium salts, and synthetic fatty acid salts are commonly used as antistatic agents. In highly insulating materials prone to static electricity, the addition of antistatic agents can reduce the volume resistance or surface resistance of the material, accelerate the dissipation of static electricity, and eliminate the risk of static discharge. 4. Process control method. Reducing the flow rate can decrease friction, thereby reducing the generation of static electricity. Therefore, when a storage tank receives and discharges hazardous chemicals, controlling the flow rate of these chemicals is also an effective way to reduce the generation of static electricity. 5. Eliminate additional sources of static electricity. When hazardous chemicals are moist or mixed with each other and passed through compressed air, the amount of static electricity generated increases. Therefore, when filling and transporting hazardous chemicals, it is necessary to prevent them from mixing with water and air, as well as from mixing with each other. 6. Eliminate static electricity in the human body. To eliminate static electricity in the human body, specific measures such as grounding, wearing anti-static shoes and anti-static clothing can be used to reduce the accumulation of static electricity on the body. In the tank area, anti-static shoes and anti-static work clothes should be worn, along with gloves and a hat. When wearing anti-static shoes, it is necessary to consider the electrical conductivity of the socks worn; conductive anti-static socks should be used to ensure that the static electricity generated by the body can flow smoothly through the anti-static shoes into the ground. Additionally, care should be taken not to apply insulating tape to the soles of the anti-static shoes. 7. Connection of pipes. There are many pipelines in the tank farm area, so anti-static measures must be taken. Generally, for pipe flange connections with four or fewer bolts, a jumper is required; those with more than four bolts do not need one ； The wires in the interlayer lining must be connected using special anti-static hoses, and it is necessary to check whether the wires inside these hoses are continuous and in good contact with the metal tubes ； A jumper wire should be installed at the swivel joint of the loading crane pipe; this jumper wire is generally made by welding round steel with a diameter of at least 8 millimeters, or by using flat metal secured with bolts ； The grounding or bonding flexible wires for the equipment should be made of copper wire ； For those connected using bolts and spring washers, additional repeated grounding should be provided, and care should be taken to avoid grease contamination and rust. 8. Pay attention to the unloading process. When filling flammable liquids into barrels, the iron barrels should be placed on a conductive surface to ensure natural grounding; the use of non-conductive rubber pads is prohibited. For oil transfer pipes made of insulating materials such as rubber and plastic, metal wire should be wrapped around the pipe surface, and it must be grounded. For temporary grounding connected using clamps (similar to battery clamps), make sure there is no contamination from paint, resin, or grease. The connection points should be kept away from areas such as loading and unloading ports where flammable vapors may be present.